Association between vertical and horizontal force-velocity-power profiles in netball players

This cross-sectional study evaluated the sprint and jump mechanical profiles of male academy rugby league players, the differences between positions, and the associations between mechanical profiles and sprint performance. Twenty academy rugby league players performed 40-m sprints and squat jumps at increasing loads (0–80 kg) to determine individual mechanical (force-velocity-power) and performance variables. The mechanical variables (absolute and relative theoretical maximal force-velocity-power, force-velocity linear relationship, and mechanical efficiency) were determined from the mechanical profiles. Forwards had significantly (p < 0.05) greater vertical and horizontal force, momentum but jumped lower (unloaded) and were slower than backs. No athlete presented an optimal jump profile. No associations were found between jump and sprint mechanical variables. Absolute theoretical maximal vertical force significantly (p < 0.05) correlated (r = 0.71–0.77) with sprint momentum. Moderate (r = −0.47) to near-perfect (r = 1.00) significant associations (p < 0.05) were found between sprint mechanical and performance variables. The largest associations shifted from maximum relative horizontal force-power generation and application to maximum velocity capabilities and force application at high velocities as distance increased. The jump and sprint mechanical profiles appear to provide distinctive and highly variable information about academy rugby league players’ sprint and jump capacities. Associations between mechanical variables and sprint performance suggest horizontal and vertical profiles differ and should be trained accordingly.

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Comparison of two measurement devices for obtaining horizontal force-velocity profile variables during sprint running

International Journal of Sports Science & Coaching ◽

10.1177/17479541211067211 ◽

2022 ◽

pp. 174795412110672

Author(s):

Erin Feser ◽

Kyle Lindley ◽

Kenneth Clark ◽

Neil Bezodis ◽

Christian Korfist ◽

...

Keyword(s):

Random Error ◽

Maximum Velocity ◽

American Football ◽

Systematic Bias ◽

Maximal Velocity ◽

Horizontal Force ◽

Time Data ◽

Measured Velocity ◽

Theoretical Maximum ◽

Force Velocity

This study established the magnitude of systematic bias and random error of horizontal force-velocity (F-v) profile variables obtained from a 1080 Sprint compared to that obtained from a Stalker ATS II radar device. Twenty high-school athletes from an American football training group completed a 30 m sprint while the two devices simultaneously measured velocity-time data. The velocity-time data were modelled by an exponential equation fitting process and then used to calculate individual F-v profiles and related variables (theoretical maximum velocity, theoretical maximum horizontal force, slope of the linear F-v profile, peak power, time constant tau, and horizontal maximal velocity). The devices were compared by determining the systematic bias and the 95% limits of agreement (random error) for all variables, both of which were expressed as percentages of the mean radar value. All bias values were within 6.32%, with the 1080 Sprint reporting higher values for tau, horizontal maximal velocity, and theoretical maximum velocity. Random error was lowest for velocity-based variables but exceeded 7% for all others, with slope of the F-v profile being greatest at ±12.3%. These results provide practitioners with the information necessary to determine if the agreement between the devices and the magnitude of random error is acceptable within the context of their specific application.

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Delineating the potential of the vertical and horizontal force-velocity profile for optimizing sport performance: A systematic review

Journal of Sports Sciences ◽

10.1080/02640414.2021.1993641 ◽

2021 ◽

pp. 1-14

Author(s):

Andrés Baena-Raya ◽

Pablo García-Mateo ◽

Amador García-Ramos ◽

Manuel A. Rodríguez-Pérez ◽

Alberto Soriano-Maldonado

Keyword(s):

Systematic Review ◽

Velocity Profile ◽

Sport Performance ◽

Horizontal Force ◽

Force Velocity

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Reliability of horizontal force–velocity–power profiling during short sprint-running accelerations using radar technology

Sports Biomechanics ◽

10.1080/14763141.2017.1386707 ◽

2017 ◽

Vol 18 (1) ◽

pp. 88-99 ◽

Cited By ~ 9

Author(s):

Kim David Simperingham ◽

John B. Cronin ◽

Simon N. Pearson ◽

Angus Ross

Keyword(s):

Horizontal Force ◽

Sprint Running ◽

Power Profiling ◽

Force Velocity

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Horizontal Force-Velocity-Power Profiling of Rugby Players

The Journal of Strength and Conditioning Research ◽

10.1519/jsc.0000000000004027 ◽

2021 ◽

Vol Publish Ahead of Print ◽

Author(s):

Casey M. Watkins ◽

Adam Storey ◽

Michael R. McGuigan ◽

Paul Downes ◽

Nicholas D. Gill

Keyword(s):

Horizontal Force ◽

Power Profiling ◽

Force Velocity ◽

Rugby Players

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Association between Sprinting Performance and Force-Velocity Mechanical Profile of Men’s and Women’s World-Class Sprinters

Proceedings ◽

10.3390/proceedings2019025033 ◽

2019 ◽

Vol 25 (1) ◽

pp. 33

Author(s):

Stavridis ◽

Paradisis

Keyword(s):

Mechanical Properties ◽

Forward Direction ◽

Horizontal Force ◽

Time Curve ◽

S 100 ◽

World Class ◽

Force Velocity ◽

Spatio Temporal ◽

The Relationship ◽

Split Time

AIM: The aim of this study was to examine the relationship between the performance of men’s and women’s finalists in the 100-m finals of IAAF World Championship 2017 and the mechanical properties of horizontal force-velocity-power (FVP) profile produced by each athlete. MATERIAL & METHOD: The spatio-temporal data from the 16 finalist sprinters (8 men and 8 women with 10.04 ± 0.12 s and 10.97 ± 0.09 s 100-m performance, respectively), were obtained from recordings of the distance-time curve in men’s and women’s 100-m finals during the IAAF World Championships 2017. The variables of horizontal FVP profile were calculated in order to determine the relationship between horizontal FVP profile [theoretical maximal values of force (F0), velocity (V0), and power (Pmax), the proportion of the theoretical maximal effectiveness of force application in the forward direction (RFmax), the rate of decrease in the ratio of horizontal force (DRF)] and the 10-m split-time, as well as the sprint running performance of men’s and women’s finalists in 100-m race. RESULTS: Spearman’s correlation analysis revealed highly negative linear associations between Pmax (r = −0.87, r2 = 0.76; p < 0.001), RFmax (r = −0.81, r2 = 0.66; p < 0.001), V0 (r = −0.78, r2 = 0.61; p < 0.001), and F0 (r = −0.66, r2 = 0.44; p = 0.005) with 100-m performance. The 10-m split-time was highly negatively linearly associated with RFmax (r = −0.98, r2 = 0.97; p < 0.001), F0 (r = −0.96, r2 = 0.93; p < 0.001), Pmax (r = −0.96, r2 = 0.91; p < 0.001), V0 (r = −0.62, r2 = 0.38; p = 0.011). DRF was not correlated with 10-m split-time or 100-m performance (p > 0.05). CONCLUSION: The mechanical properties of FVP profile strongly influenced the 100-m performance of men’s and women’s world-class sprinters. This study highlights the importance of the technical capability of world-class athletes to effectively orient the horizontal force onto the supporting ground during the initial sprint-acceleration.

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Changes to horizontal force-velocity and impulse measures during sprint running acceleration with thigh and shank wearable resistance

Journal of Sports Sciences ◽

10.1080/02640414.2021.1882771 ◽

2021 ◽

pp. 1-9

Author(s):

Erin H. Feser ◽

Neil E. Bezodis ◽

Jono Neville ◽

Paul Macadam ◽

Aaron M. Uthoff ◽

...

Keyword(s):

Horizontal Force ◽

Sprint Running ◽

Force Velocity

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Magnetic suspension mechanism using rotary permanent magnets

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209412 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 977-983

Author(s):

Koichi Oka ◽

Kentaro Yamamoto ◽

Akinori Harada

Keyword(s):

Permanent Magnets ◽

Suspension System ◽

Magnetic Suspension ◽

Horizontal Force ◽

Mechanical Contact ◽

New Type ◽

Magnetic Suspension System

This paper proposes a new type of noncontact magnetic suspension system using two permanent magnets driven by rotary actuators. The paper aims to explain the proposed concept, configuration of the suspension system, and basic analyses for feasibility by FEM analyses. Two bar-shaped permanent magnets are installed as they are driven by rotary actuators independently. Attractive forces of two magnets act on the iron ball which is located under the magnets. Control of the angles of two magnets can suspend the iron ball stably without mechanical contact and changes the position of the ball. FEM analyses have been carried out for the arrangement of two permanent magnets and forces are simulated for noncontact suspension. Hence, successfully the required enough force against the gravity of the iron ball can be generated and controlled. Control of the horizontal force is also confirmed by the rotation of the permanent magnets.

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Fore-Aft Forces in Tire-Wheel Assemblies Generated by Unbalances and the Influence of Balancing

Tire Science and Technology ◽

10.2346/1.2141713 ◽

1991 ◽

Vol 19 (3) ◽

pp. 142-162 ◽

Cited By ~ 4

Author(s):

D. S. Stutts ◽

W. Soedel ◽

S. K. Jha

Keyword(s):

Mathematical Model ◽

Elastic Foundation ◽

Torsional Oscillation ◽

Vertical Direction ◽

Torsional Stiffness ◽

Rolling Motion ◽

Vertical Force ◽

Horizontal Force ◽

Wheel Rim ◽

Open Question

Abstract When measuring bearing forces of the tire-wheel assembly during drum tests, it was found that beyond certain speeds, the horizontal force variations or so-called fore-aft forces were larger than the force variations in the vertical direction. The explanation of this phenomenon is still somewhat an open question. One of the hypothetical models argues in favor of torsional oscillations caused by a changing rolling radius. But it appears that there is a simpler answer. In this paper, a mathematical model of a tire consisting of a rigid tread ring connected to a freely rotating wheel or hub through an elastic foundation which has radial and torsional stiffness was developed. This model shows that an unbalanced mass on the tread ring will cause an oscillatory rolling motion of the tread ring on the drum which is superimposed on the nominal rolling. This will indeed result in larger fore-aft than vertical force variations beyond certain speeds, which are a function of run-out. The rolling motion is in a certain sense a torsional oscillation, but postulation of a changing rolling radius is not necessary for its creation. The model also shows the limitation on balancing the tire-wheel assembly at the wheel rim if the unbalance occurs at the tread band.

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